Comparison of effect of granules and herbs of Bu-Shen-Yi-Qi-Tang on airway inflammation in asthmatic mice.

Background: Bu-Shen-Yi-Qi-Tang (BSYQT), which is prescribed on the basis of clinical experience, is commonly used in clinics of traditional Chinese medicine (TCM) for asthma treatment. The components of BSYQT include Radix Astragali (RA), Herba Epimedii (HE) and Radix Rehmanniae (RR). The aim of this study was to compare the effect of granules and herbs of BSYQT on airway inflammation in asthmatic mice.
Methods: Sixty female BALB/c mice were randomly divided into the normal control (NC) group, asthmatic group (A), decoction of granules of BSYQT treatment group (GD), decoction of herbs of BSYQT treatment group (HD), and dexamethasone treatment group (DEX). The mouse asthmatic model was induced by ovalbumin (OVA) sensitization and challenge. GD and HD of BSYQT as well as DEX were prepared and administered by intragastric infusion. Airway hyperresponsiveness (AHR) to methacholine (Mch), lung histopathology analysis, inflammatory mediators in serum (IL-4, IL-5, IL-17A, IFN-γ, and eotaxin) and in lung (IL-4, IL-5, IFN-γ, and eotaxin) were selected for investigation and comparison.
Results: Both GD and HD treatment could decrease airway resistance (RL) and increase dynamic compliance (Cdyn) to Mch compared with the A group (P < 0.05). HD treatment was more effective in RL reduction than Mch at doses of 3.125 and 6.25 mg/ml (P < 0.05) and in Cdyn increase at Mch doses of 6.25 and 12.5 mg/ml (P < 0.05). There were no marked differences in RL reduction and Cdyn improvement between mice in HD and DEX groups (P > 0.05). Both GD and HD treatment markedly attenuated lung inflammation (P < 0.05), and HD treatment demonstrated more significant therapeutic function in alleviating lung inflammation than that of GD and DEX treatment (P < 0.05). Both GD and HD treatment resulted in a significant reduction in IL-4 and IL-17A levels and an increase in the IFN-γ level in serum compared with the A group (P < 0.05). The effect of HD in lowering the IL-4 and IL-17A level was significantly greater than that of GD (P < 0.05), and was not significantly different from DEX (P > 0.05). HD treatment significantly reduced the serum level of IL-5 and eotaxin compared with the A group (P < 0.05), however, mice in the GD treatment group did not demonstrate this effect. GD and HD treatment significantly reduced IL-4 and eotaxin mRNA expression compared with the A group (P < 0.05). HD treatment significantly reduced IL-5 mRNA expression compared with the A group (P < 0.05). There was a significant difference between the GD and HD treatment groups in reducing IL-5 and eotaxin mRNA expression (P < 0.05). HD treatment was more effective in down-regulation of IL-5 in serum and eotaxin level both in serum and lung than DEX (P < 0.05). Compared with the A group, an obvious increase in mRNA expression of IFN-γ was observed in both the GD and HD treatment groups (P < 0.05). However, the effect of HD treatment on increase of IFN-γ mRNA expression was more apparent than GD and DEX treatment (P < 0.05).
Conclusions: Both GD and HD treatment could decrease AHR, attenuate lung inflammation, reduce IL-4, IL-5, IL-17A, and eotaxin levels and increase IFN-γ levels in asthmatic mice. HD treatment manifests more remarkable inhibitory effects on asthmatic inflammation than GD treatment, which could provide a guide for further research on the screening of the material basis of the best anti-inflammatory effect of BSYQT.